How much water was in your coffee this morning? You might be surprised to learn that the answer is 140 litres. Even I didn't drink that much. But as this environmental scientist explains: "That is the amount of water used in growing, producing, packaging and shipping the beans." His book encourages us to look at such "virtual water" embedded in commodities, which lends a surprising new angle to global trade. (A country that imports wheat is in effect importing the water needed to grow it.) Allan distinguishes usefully, too, between "blue water" (rivers and lakes) versus "green water" (in plants and soil), the latter hard to cost.

Allan considers water policy in Spain, the US, Egypt, and China (in water terms, the one-child policy "saved the world", he claims provocatively), and argues that the "hydrological mission" of irrigation and damming is always wrong, while explaining the connections between water, food and "energy security". The book is rather rambling, but it is friendly and clear. I was only saddened to see yet again the story of the poor frog, who according to the cliché won't jump out of a slowly heated pan of water. This amphibian libel must end now.

The Fair Trade Revolution, edited by John Bowes (Pluto Press, £12.99)

If the foregoing wasn't enough to harsh your coffee mellow, consider the contribution to global warming made by flying coffee beans all over the place. That is what one of the best contributions to this collection brings up, in useful counterpoint to the celebratory nature of the rest. Of course, there are things worth celebrating: heartwarming stories from Harriet Lamb and Rachel Archer about happier farmers in Rwanda, Tanzania and Nicaragua, and regular approving mentions (veering close to puffery) of decisions to go "fair" by big companies such as Cadbury or Tate & Lyle. Matt North explains why, at Sainsbury's, he decided to make all their bananas Fairtrade, while Jonathan Rosenthal surveys earlier "ethical shopping" movements, for example a Quaker initiative in 1790 to sell "slave-free cotton, fruit and vegetables".

It is Tomy Mathew, though, who sounds the elegant warning about the counterproductive climatic effects (such as drought) of flying food around at all. Luckily, before we wean ourselves off caffeine completely, Mathew argues that we first have to drink "far greater amounts of Fairtrade coffee" than at present. I'm doing my best.

The Book of English Place Names, by Caroline Taggart (Ebury Press, £9.99)

This amiable volume does exactly what it says on the tin: strolling at leisure through the names of English towns and villages and explaining their origins: Roman, Celtic, Saxon or otherwise. Taggart also collects examples into wider themes such as how names evolve "through mumbling and confusion", the Norwegian influence on the northwest, tautological placenames ("Bredon" means "hill hill"), and placenames we might snigger at, though they have "perfectly sensible derivations": Badgers Mount, Great Snoring, Nasty, and Ogle.

What is striking is the number of placenames apparently bestowed by people who would rather be somewhere else: Pity Me (for living here), Morpeth ("It almost certainly means 'path where a murder or murders took place', but no one seems to know why"), Snape ("boggy ground"), Hungerford ("a ford associated with hunger, because the surrounding land was infertile"), and the splendid Unthank: "It really does mean 'thankless' or 'unthankful'. So it is either land occupied by squatters . . . or land that was unrewarding to cultivate." And so our forbears' talent for dissatisfaction is preserved nicely in these little nuggets of virtual moaning.